Command-curable composition

Abstract

A light-curable dental cement composition contains (a) the reaction product of vinyl phosphonyl chloride and pentane 1,5 diol, (b) a photopolymerisation initiator, (c) ion-leachable aluminosilicate glass powder, (d) poly(vinyl phosphonic acid), (e) bisGMA as a photopolymerisable dimethacrylate resin, and water, inert filler and silanising agent. Upon mixing, glass is added last, the composition is put in place and, when ready, it is light-irradiated for 30 or 40 seconds to polymerise (e). The composition is immediately firm and the phosphonate groups adhere to tooth material while further slow curing by acid-base reaction continues.

We claim: 
     
       1. A command-curable composition comprising: (a) a partly esterified phosphonic acid being equivalent to the reaction product between a precursor of a poly(vinyl phosphonic acid) and a polyhydric alcohol, in the mole ratio (0.2-5.0) phosphonic acid groups: 1 esterifying group;   (b) an initiator;   (c) cation-leachable glass powder and/or amphoteric or basis metal oxide;   (d) poly(vinyl phosphonic acid); and   (e) a bulky molecule compatible with component (a) and having at least two vinyl groups through which it may cross-link/polymerize to yield a completely hydrophobic polymer, said bulky molecule being a dimethacrylate;   said partly esterified phosphonic acid (a) being present in an amount to promote adhesion and to promote compatibility and miscibility of the other components of the composition;   the weight ratio of component (d) to component (c) being from 1:2 to 1:5.5; and   the weight ratio of component (d) to component (a)+component (e) being from 1:1.3 to 1:2.7.   
     
     
       2. A command-curable composition according to claim 1, further comprising water. 
     
     
       3. A command-curable composition according to claim 1, wherein the OH groups in the alcohol are interconnected via from two to twenty organic backbone atoms. 
     
     
       4. A command-curable composition according to claim 3, wherein the OH groups in the alcohol are interconnected via carbon atoms with oxygen atoms interposed at least every fifth carbon atom. 
     
     
       5. A command-curable composition according to claim 3, wherein the said mole ratio is (0.5-1.5):1. 
     
     
       6. A command-curable composition according to claim 5, wherein the said mole ratio is (0.8-1.2):1. 
     
     
       7. A command-curable composition according to claim 1, wherein the said precursor is vinyl phosphonic dichloride. 
     
     
       8. A command-curable composition according to claim 1, wherein component (c) is aluminosilicate glass powder. 
     
     
       9. A command-curable composition according to claim 8, wherein the glass powder (c) has an Si:Al atomic ratio of (0.2-0.6):1 or (0.6-2):1. 
     
     
       10. A command-curable composition according to claim 1, wherein the glass powder consists of particles substantially all of which are smaller than 100 microns. 
     
     
       11. A command-curable composition according to claim 1, wherein component (c) is MgO deactivated at at least 900° C. 
     
     
       12. A command-curable composition according to claim 1, further comprising a filler. 
     
     
       13. A command-curable composition according to claim 1, further comprising a silanizing agent. 
     
     
       14. A pack comprising all the components of a composition according to claim 1, so presented as not to react prematurely.